. >> i am not violating any law. >> in two san francisco bay area cities known for crime oakland and rimmond westbound. >> but now, police in both of these cities have high tech back-ups. electronic ears listening for gunfire, 24/7. he lectronic eyes monitoring police and perps alike. even the cars on this street. officer chris tong is patrolling the streets of richmond that. ding you hear is the sound of a license plate reader. watch what happens when he passes a stolen vehicle. >> it's just triggered on an unoccupied vehicle. turn around and take a look what we've got here. >> the unoccupied vehicle was a stolen nissan sentra caught by the high-speed infrared camera, a series of computer algorithims identified the vehicle's license plate and checked it against a database of wanted cars all in a matter of seconds. >> license plate reader keeps track of a lot of the information that the vehicle was indeed stolen when the vehicle was reported stolen, when we located the vehicle. center. >> these cameras scan several hundred to a thousand plates an hour. much more than an officer could